We’ve had a blitz of platypus genome papers this week, with a brand new article on the platypus genome sequence in Nature and several papers on specific aspects of this genome showing up in Genome Research. I hope to cover a couple of these in the next week. It’s been a while since my last update because I’ve been very busy, but I’ll take a look at the platypus genome paper itself tomorrow and hopefully follow-up Sunday or Monday with some of the information from Genome Research.

Of course this discovery has led to more bad reporting, and from reading the news outlet articles it looks like the scientists involved are contributing to some of it! Some of the things they are saying are not wrong, but possibly misleading. I’ll go into that a little bit tomorrow. For now let’s say I keep seeing the word “primitive”, and the New York Times refers to monotremes as “offshoots of the main mammalian lineage”. Well, I personally think the placentals and marsupials are branches off that most noble main mammalian lineage, the sadly extinct multituberculates.

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ResearchBlogging.orgTHE MICROVIRUSES are positive-strand DNA viruses with very small genomes, typified by ΦX174 with 5,400 base pairs and nine genes. Cramming this many genes into that short a sequence requires overlapping reading frames, with gene B contained inside gene A, and gene E contained inside gene D.1 These nested genes are frame-shifted compared to the gene that contains them.

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ResearchBlogging.orgWHILE MANY NICHES are ever-present in vertebrate-dominated ecosystems, sometimes we find an extinct group that was unique in some way. At various times in the past carnivores have evolved saber-teeth, but currently there are no saber-toothed predators (although the clouded leopard may be working on it). In a previous post I mentioned Simocyon, a cursorial generalized carnivore that retained arboriality in order to escape from larger predators, including the saber-toothed cats. Today I will write about Thylacoleo carnifex, the so-called marsupial lion.

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I COVERED the volvocine algae recently and promised a post on some of the genes involved in the evolution of multicellularity in this group. We still know relatively little about the genomes of volvocine algae, but research has picked out three genes involved in the evolution of multicellularity. These are invA, glsA, and regA.

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SCIENCE MAGAZINE has a busy day today. Appearing in the current issue are two important articles.

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ResearchBlogging.orgMOST OF OUR study of gene networks has been done by comparison of related species to reconstruct network evolution and by knocking out specific genes to determine what the effects of their absence are. In a new paper Isalan and coworkers try something new, reprogramming genetic networks in Escherichia coli and examining the mutants to detect viability and any possible benefits to genetic pathway modification.

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LOTS OF GOOD stuff appearing in the blogosphere this past week. PZ Myers has a post on how chromosome counts change and can contribute to speciation. Emile writes about beetles that chemically enslave ants. On the paleontological side of things Darren Naish wraps up his series on British cat species and Brian Switek reports on a new study showing that elephants are descended from aquatic ancestors, with links to blog coverage at other sites.

I will post tomorrow about the results of an experimental addition of links to gene networks in bacteria and later this week a survey of some of the genes involved in developing multicellularity in volvocine algae.

ResearchBlogging.orgIN MANY CASES even large phenotypic changes can occur without much genetic change. However, occasionally a species will be placed in a situation in which its ancestor’s genes are insufficient, and if the species possesses a gene that can be co-opted into a new role, selection can favor evolution of new genes and a corresponding radiation of species. The Pieridae family of butterflies lay their eggs on plants in the Brassicaceae family, which contains mustards and cabbages. These plants have evolved to produce compounds that are harmless in undamaged leaves, but when a leaf is damaged are converted to a potent insecticide. The pierids evolved a deactivating protein that diverts the chemical reaction to produce nontoxic products. This gene evolved shortly after the plants themselves, and would have allowed these butterflies’ larvae to feed upon these plants with little competition.

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I PREVIOUSLY POSTED on this topic but the author of the article objected, feeling that his copyright had been violated. Unfortunately he has been unforthcoming about his specific objections and how I could correct the post, so I decided to write a second version. It is possible that my first post may have violated copyright by covering too much information. As I was writing my goal was to do the paper justice. It was the culmination of years of research, and is preceded by multiple other articles. It may be that in trying to be correct and thorough I included too much information. In this rewrite I have omitted a good deal of information and brought in a variety of other sources to cover the geography of the region.

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I’ve mentioned worms and viruses here before, but this is the first time Trojans have earned a mention!

Yesterday I started seeing a weird error message on my computer saying something about kavo.exe not being able to run. This made me think, “Hmm, I’m not sure I want that to run. . .” Indeed, after searching for it I found out I did not!

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